// Copyright (c) 2011 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef NET_PROXY_PROXY_BYPASS_RULES_H_
#define NET_PROXY_PROXY_BYPASS_RULES_H_

#include <string>
#include <vector>

#include "base/macros.h"
#include "net/base/net_export.h"
#include "url/gurl.h"

namespace net {

// ProxyBypassRules describes the set of URLs that should bypass the proxy
// settings, as a list of rules. A URL is said to match the bypass rules
// if it matches any one of these rules.
class NET_EXPORT ProxyBypassRules {
public:
    // Interface for an individual proxy bypass rule.
    class NET_EXPORT Rule {
    public:
        Rule();
        virtual ~Rule();

        // Returns true if |url| matches the rule.
        virtual bool Matches(const GURL& url) const = 0;

        // Returns a string representation of this rule. This is used both for
        // visualizing the rules, and also to test equality of a rules list.
        virtual std::string ToString() const = 0;

        // Creates a copy of this rule. (Caller is responsible for deleting it)
        virtual Rule* Clone() const = 0;

        bool Equals(const Rule& rule) const;

    private:
        DISALLOW_COPY_AND_ASSIGN(Rule);
    };

    typedef std::vector<const Rule*> RuleList;

    // Note: This class supports copy constructor and assignment.
    ProxyBypassRules();
    ProxyBypassRules(const ProxyBypassRules& rhs);
    ~ProxyBypassRules();
    ProxyBypassRules& operator=(const ProxyBypassRules& rhs);

    // Returns the current list of rules. The rules list contains pointers
    // which are owned by this class, callers should NOT keep references
    // or delete them.
    const RuleList& rules() const { return rules_; }

    // Returns true if |url| matches any of the proxy bypass rules.
    bool Matches(const GURL& url) const;

    // Returns true if |*this| is equal to |other|; in other words, whether they
    // describe the same set of rules.
    bool Equals(const ProxyBypassRules& other) const;

    // Initializes the list of rules by parsing the string |raw|. |raw| is a
    // comma separated list of rules. See AddRuleFromString() to see the list
    // of supported formats.
    void ParseFromString(const std::string& raw);

    // This is a variant of ParseFromString, which interprets hostname patterns
    // as suffix tests rather than hostname tests (so "google.com" would actually
    // match "*google.com"). This is only currently used for the linux no_proxy
    // evironment variable. It is less flexible, since with the suffix matching
    // format you can't match an individual host.
    // NOTE: Use ParseFromString() unless you truly need this behavior.
    void ParseFromStringUsingSuffixMatching(const std::string& raw);

    // Adds a rule that matches a URL when all of the following are true:
    //  (a) The URL's scheme matches |optional_scheme|, if
    //      |!optional_scheme.empty()|
    //  (b) The URL's hostname matches |hostname_pattern|.
    //  (c) The URL's (effective) port number matches |optional_port| if
    //      |optional_port != -1|
    // Returns true if the rule was successfully added.
    bool AddRuleForHostname(const std::string& optional_scheme,
        const std::string& hostname_pattern,
        int optional_port);

    // Adds a rule that bypasses all "local" hostnames.
    // This matches IE's interpretation of the
    // "Bypass proxy server for local addresses" settings checkbox. Fully
    // qualified domain names or IP addresses are considered non-local,
    // regardless of what they map to (except for the loopback addresses).
    void AddRuleToBypassLocal();

    // Adds a rule given by the string |raw|. The format of |raw| can be any of
    // the following:
    //
    // (1) [ URL_SCHEME "://" ] HOSTNAME_PATTERN [ ":" <port> ]
    //
    //   Match all hostnames that match the pattern HOSTNAME_PATTERN.
    //
    //   Examples:
    //     "foobar.com", "*foobar.com", "*.foobar.com", "*foobar.com:99",
    //     "https://x.*.y.com:99"
    //
    // (2) "." HOSTNAME_SUFFIX_PATTERN [ ":" PORT ]
    //
    //   Match a particular domain suffix.
    //
    //   Examples:
    //     ".google.com", ".com", "http://.google.com"
    //
    // (3) [ SCHEME "://" ] IP_LITERAL [ ":" PORT ]
    //
    //   Match URLs which are IP address literals.
    //
    //   Conceptually this is the similar to (1), but with special cases
    //   to handle IP literal canonicalization. For example matching
    //   on "[0:0:0::1]" would be the same as matching on "[::1]" since
    //   the IPv6 canonicalization is done internally.
    //
    //   Examples:
    //     "127.0.1", "[0:0::1]", "[::1]", "http://[::1]:99"
    //
    // (4)  IP_LITERAL "/" PREFIX_LENGHT_IN_BITS
    //
    //   Match any URL that is to an IP literal that falls between the
    //   given range. IP range is specified using CIDR notation.
    //
    //   Examples:
    //     "192.168.1.1/16", "fefe:13::abc/33".
    //
    // (5)  "<local>"
    //
    //   Match local addresses. The meaning of "<local>" is whether the
    //   host matches one of: "127.0.0.1", "::1", "localhost".
    //
    // See the unit-tests for more examples.
    //
    // Returns true if the rule was successfully added.
    bool AddRuleFromString(const std::string& raw);

    // This is a variant of AddFromString, which interprets hostname patterns as
    // suffix tests rather than hostname tests (so "google.com" would actually
    // match "*google.com"). This is used for KDE which interprets every rule as
    // a suffix test. It is less flexible, since with the suffix matching format
    // you can't match an individual host.
    //
    // Returns true if the rule was successfully added.
    //
    // NOTE: Use AddRuleFromString() unless you truly need this behavior.
    bool AddRuleFromStringUsingSuffixMatching(const std::string& raw);

    // Converts the rules to string representation. Inverse operation to
    // ParseFromString().
    std::string ToString() const;

    // Removes all the rules.
    void Clear();

    // Sets |*this| to |other|.
    void AssignFrom(const ProxyBypassRules& other);

private:
    // The following are variants of ParseFromString() and AddRuleFromString(),
    // which additionally prefix hostname patterns with a wildcard if
    // |use_hostname_suffix_matching| was true.
    void ParseFromStringInternal(const std::string& raw,
        bool use_hostname_suffix_matching);
    bool AddRuleFromStringInternal(const std::string& raw,
        bool use_hostname_suffix_matching);
    bool AddRuleFromStringInternalWithLogging(const std::string& raw,
        bool use_hostname_suffix_matching);

    RuleList rules_;
};

} // namespace net

#endif // NET_PROXY_PROXY_BYPASS_RULES_H_
